One of the giants to emerge from the New German Cinema of the 1970’s was director Werner Herzog, with wild visions like “Aguirre, the Wrath of God,” “Fitzcarraldo,” and “Nosferatu” — a dreamlike cinema that, with these films in particular, explore the nature of obsession in revelatory ways. His muse for this batch of movies was Klaus Kinski, a notoriously difficult and eccentric German actor renowned for his temper tantrums, violent, erratic outbursts and refusal to take direction from anyone.

In a collaboration that lasted for almost two decades and resulted in five movies, Herzog molded Kinski’s madness into some of the most hypnotic performances ever captured on film, with an almost palpable intensity that to this day is rigorously unique. Whether a Spanish conquistador, a European bourgeois, or bloodsucking creature of the night, Kinski always lost himself in his roles and emerged closer to what Herzog refers to as “Ecstatic Truth,” a poetic reality with more veracity than any documentary.

Herzog’s latest film, “My Best Fiend,” is his very personal portrait of his professional collaborator. Their pairing pushed both of them to creative extremes, and even thoughts of murder; but time and again the result was always their best work. New Yorker Films is distributing “My Best Fiend,” currently screening at New York’s Film Forum.

indieWIRE: The footage in “My Best Fiend” of Kinski ranting on the set of “Aguirre” is one of the high points of your documentary.

Werner Herzog: That was Les Blank, and those were some out-takes from his documentary “Burden of Dreams.” And also, I have to point back to Les Blank again: some of the finest stuff in the film — like at the end, with Kinski playing with the butterfly — that was his footage, which was also out-takes, and I do not understand why he overlooked such unbelievable footage and he didn’t use it in “Burden of Dreams.”

iW: I guess he had so much good stuff on Kinski.

Herzog: Well, yes, let’s face it: the man really had too much good stuff. He would have ended up with a three-hour movie.

iW: I was recently watching Blank’s film “Werner Herzog Eats his Shoe”…

Herzog: Which was actually meant for the family album [laughs], but he released it anyway.

iW: And I found it fascinating that the reason you literally ate your shoe was because you bet Errol Morris that he would never make his first film. What do you think of Morris’ documentaries, especially in light of your own recent work and your own particular philosophy about documentary film?

Herzog: I’m very pleased – he’s one of the finest we have anywhere around, and he has never let us down, has never made a bad or mediocre film. Everything he makes is very, very good.

iW: What do you think of his approach to the documentary film?

Herzog: Thank God he does it that way, because I’ve always postulated a new position in documentary filmmaking – but let’s say filmmaking generally, because I’m sick and tired of what I see on television. And I’m also sick and tired of cinema v